1. Field of the Invention
The present invention concerns puncture and tear resistant material particularly suitable for use in vehicular convertible tops, and convertible tops constructed with such material.
2. Background of the Invention
Vehicular roofs, or tops, that deploy between an erected position shielding the vehicle's passenger compartment and its occupants, and a retracted position stored in or about the vehicle, have long been popular for permitting the vehicle's passengers to selectively expose or shield themselves from the weather and from view. Erectable and retractable vehicular roofs are deployed by diverse mechanical mechanisms variously involving the mechanical actions of sliding, telescoping, springing into position (e.g., the "hardtop convertible"), and folding.
Almost all erectable roofs for automobiles are constructed as conventional convertible tops made from foldable sheet material (normally weatherproof fabric) and collapsible frames. Conventional convertible tops for automobiles are lightweight, compact when folded, amenable to powered positioning control, and reasonably satisfactory when erected to shield and protect the automobile occupants from weather and noise.
The conventional automotive convertible top has, however, certain limitations. It exhibits only limited resistance to puncture and tearing, whether accidental or malicious. Criminal forced entry into automotive interiors in order to steal items located therein, such as the automobile's radio, is unfortunately very prevalent in some urban areas at the present time. If the automobile has a convertible top then the criminal simply slashes the top with a knife or other tool to gain access to the automobile's doorlocks, and ultimately to the automobile's interior. A conventional convertible top not only presents but scant impediment to forced entry, but is all but unusable in high crime areas because the top will soon be maliciously ruined during forced entry. This is true regardless of whether or not the automobile's interior ever contains anything worth stealing.
Other, more subtle, problems exist with the limited strength of a conventional automotive convertible top. When an automobile is involved in a serious accident then its occupants may be thrown from the passenger compartment, or foreign bodies may penetrate into the passenger compartment, much more readily through an erected convertible top than through a modern steel automotive roof.
A conventional convertible top cannot withstand high aerodynamic forces as well as a steel roof. Even convertible tops of high quality are subject to delamination, tearing, or being ripped from their affixation to the convertible frame and/or the automobile itself when exposed, while erected, to the aerodynamic forces resulting from travel at very high speeds. Destruction of a convertible top due to aerodynamic forces can occur whether or not the automobile's windows are up or down. However, catastrophic failure of an erected convertible top is typically more precipitous, spectacular, and dangerous when the automobile's windows are down. In such a case a convertible top may tear completely away from the automobile within the period of a few seconds. Even when high speeds and high aerodynamic forces sufficient to induce catastrophic failure of a convertible top are never encountered, the aerodynamic forces experienced by an erected convertible top tend over time to stretch the top and loosen its mountings.
Accordingly, it would be desirable if most of the advantages, and the widespread consumer acceptance, of a conventional convertible top could be preserved while somehow strengthening the top against failure from excessive penetration and/or aerodynamic forces.
It is known to provide repositionable and removable roofs for vehicles that, nonetheless to their ability to assume both erected and storage positions, present high strength including resistance to penetration.
U.S. Pat. Ser. No. 1,289,969 for a CANOPY to Tichenor shows a telescoping mesh screen canopy particularly for use on a baby carriage. The screen material of the canopy is not flexible, and is correspondingly not folded. The interior of the baby carriage is vented through the screen canopy. Accordingly, the canopy is not combined with waterproof shielding such as fabric.
U.S. Pat. Ser. No. 2,623,779 for an AUTOMATIC CONVERTIBLE STEEL TOP to Catell shows telescoping steel sections forming a retractable steel roof for an automobile. Although presenting the strength and puncture resistance that is inherent to sheet steel, the retractable steel roof requires a special mechanism to be extended for use and retracted for storage. Although it is called a "top", the deployment and support structure of the retractable steel roof is substantially dissimilar to a normal fabric automotive convertible top.
U.S. Pat. Ser. No. 1,860,463 for an AUTOMOTIVE TOP to Kaplan, et al. again shows an automotive retractable roof made of folding steel plates. The roof is again of substantially unique construction, and is not susceptible of being retrofitted to automobiles using conventional fabric convertible tops.
High-strength repositionable vehicular roofs may in general be both erected and retracted, but are not folded and unfolded along semi-random fold lines in the manner of a conventional, flexible fabric, convertible top. It is desirable that a high-strength vehicular roof should be easily and semi-randomly foldable because erection and retraction are simple and reliable. Furthermore, erection and retraction may be power assisted by relatively simpler mechanisms than those which control the deployment of rigid repositionable automobile roofs.
It is additionally known to make use of steel mesh in automotive roofs, including in wood- and tar-containing roofs as were common upon automobiles during the 1920's and 1930's. The metal screen that was used within such roofs, or sometimes in addition to such roofs, was commonly neither flexible nor convertible. However, it was occasionally removable. U.S. Pat. Ser. No. 1,354,987 for an AUTOMOBILE SCREEN to Miller shows a screen, evidently somewhat flexible, which snaps over the existing roof and windows of an automobile in order to keep out insects. The screen is, however, not convertible in the sense that it may be erected and retracted, folded and unfolded, and stored while still attached to the automobile. The screen of Miller is also not attached to any structural members of the automotive roof.
In an art area that is totally separate and distinct from convertible tops but that is also of relevance to the present invention, flexible armor made from interlinked metal rings or metal pieces, commonly called chain mail, has been known since medieval times. Chain mail has not commonly been used for armor since the battle of Agincourt in 1415 because it may be penetrated by a metal-tipped lance, arrow, or ballistic projectile.
A modern use of chain mail exists, however, in the "shark suit" product of Neptumic, Inc. P.O. Box 7870, San Diego, Calif. 92107. The chain mail used in this product is described in U.S. Pat. Ser. No. 3,284,806 for a PROTECTIVE GARMENT to D. O. Prasser. In use for a "shark suit" a diver dons a soft armor inner garment, preferably made of laminated Kevlar.RTM.fibre (trademark of DuPont Company). An outer garment made of chain mail is donned over the top of the soft armor. The chain mail guards against penetration of the teeth of sharks while the soft armor distributes the force of any shark bites over a wider area of the body. Divers have tested the suit against the attacks of common sharks ranging to six feet in length without incurring serious injury. An improved "shark suit" where armored panels are embedded in a chain mail garment worn exteriorly of a wetsuit is described in U.S. Pat. Ser. No. 4,356,569 for an ARMORED SKIN DIVING SUIT to Jeremiah Sullivan.